سنن النسائي

It was narrated that Jabir bin Samurah said: "We used to pray behind the Messenger of Allah (ﷺ) and we would greet (others) with our hands. He said: 'What is the matter with those who greet (others) with their hands as if they were tails of wild horses? It is sufficient for any one of you to put his hand on his thigh and say: "As-salamu 'alaikum, as-salamu 'alaikum."